/*
 * Copyright (C) 2013 readyState Software Ltd
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.geminno.Utils;

import java.lang.reflect.Method;

import android.annotation.SuppressLint;
import android.annotation.TargetApi;
import android.app.Activity;
import android.content.Context;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.util.DisplayMetrics;
import android.util.TypedValue;
import android.view.Gravity;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.FrameLayout.LayoutParams;

/**
 * Class to manage status and navigation bar tint effects when using KitKat
 * translucent system UI modes.
 *
 */
public class SystemBarTintManager {

    static {
	// Android allows a system property to override the presence of the
	// navigation bar.
	// Used by the emulator.
	// See
	// https://github.com/android/platform_frameworks_base/blob/master/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java#L1076
	if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
	    try {
		Class c = Class.forName("android.os.SystemProperties");
		Method m = c.getDeclaredMethod("get", String.class);
		m.setAccessible(true);
		sNavBarOverride = (String) m.invoke(null, "qemu.hw.mainkeys");
	    } catch (Throwable e) {
		sNavBarOverride = null;
	    }
	}
    }

    /**
     * The default system bar tint color value.
     */
    public static final int DEFAULT_TINT_COLOR = 0x99000000;

    private static String sNavBarOverride;

    private final SystemBarConfig mConfig;
    private boolean mStatusBarAvailable;
    private boolean mNavBarAvailable;
    private boolean mStatusBarTintEnabled;
    private boolean mNavBarTintEnabled;
    private View mStatusBarTintView;
    private View mNavBarTintView;

    /**
     * Constructor. Call this in the host activity onCreate method after its
     * content view has been set. You should always create new instances when
     * the host activity is recreated.
     *
     * @param activity
     *            The host activity.
     */
    @TargetApi(19)
    public SystemBarTintManager(Activity activity) {

	Window win = activity.getWindow();
	ViewGroup decorViewGroup = (ViewGroup) win.getDecorView();

	if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
	    // check theme attrs
	    int[] attrs = { android.R.attr.windowTranslucentStatus,
		    android.R.attr.windowTranslucentNavigation };
	    TypedArray a = activity.obtainStyledAttributes(attrs);
	    try {
		mStatusBarAvailable = a.getBoolean(0, false);
		mNavBarAvailable = a.getBoolean(1, false);
	    } finally {
		a.recycle();
	    }

	    // check window flags
	    WindowManager.LayoutParams winParams = win.getAttributes();
	    int bits = WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS;
	    if ((winParams.flags & bits) != 0) {
		mStatusBarAvailable = true;
	    }
	    bits = WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION;
	    if ((winParams.flags & bits) != 0) {
		mNavBarAvailable = true;
	    }
	}

	mConfig = new SystemBarConfig(activity, mStatusBarAvailable,
		mNavBarAvailable);
	// device might not have virtual navigation keys
	if (!mConfig.hasNavigtionBar()) {
	    mNavBarAvailable = false;
	}

	if (mStatusBarAvailable) {
	    setupStatusBarView(activity, decorViewGroup);
	}
	if (mNavBarAvailable) {
	    setupNavBarView(activity, decorViewGroup);
	}

    }

    /**
     * Enable tinting of the system status bar.
     *
     * If the platform is running Jelly Bean or earlier, or translucent system
     * UI modes have not been enabled in either the theme or via window flags,
     * then this method does nothing.
     *
     * @param enabled
     *            True to enable tinting, false to disable it (default).
     */
    public void setStatusBarTintEnabled(boolean enabled) {
	mStatusBarTintEnabled = enabled;
	if (mStatusBarAvailable) {
	    mStatusBarTintView
		    .setVisibility(enabled ? View.VISIBLE : View.GONE);
	}
    }

    /**
     * Enable tinting of the system navigation bar.
     *
     * If the platform does not have soft navigation keys, is running Jelly Bean
     * or earlier, or translucent system UI modes have not been enabled in
     * either the theme or via window flags, then this method does nothing.
     *
     * @param enabled
     *            True to enable tinting, false to disable it (default).
     */
    public void setNavigationBarTintEnabled(boolean enabled) {
	mNavBarTintEnabled = enabled;
	if (mNavBarAvailable) {
	    mNavBarTintView.setVisibility(enabled ? View.VISIBLE : View.GONE);
	}
    }

    /**
     * Apply the specified color tint to all system UI bars.
     *
     * @param color
     *            The color of the background tint.
     */
    public void setTintColor(int color) {
	setStatusBarTintColor(color);
	setNavigationBarTintColor(color);
    }

    /**
     * Apply the specified drawable or color resource to all system UI bars.
     *
     * @param res
     *            The identifier of the resource.
     */
    public void setTintResource(int res) {
	setStatusBarTintResource(res);
	setNavigationBarTintResource(res);
    }

    /**
     * Apply the specified drawable to all system UI bars.
     *
     * @param drawable
     *            The drawable to use as the background, or null to remove it.
     */
    public void setTintDrawable(Drawable drawable) {
	setStatusBarTintDrawable(drawable);
	setNavigationBarTintDrawable(drawable);
    }

    /**
     * Apply the specified alpha to all system UI bars.
     *
     * @param alpha
     *            The alpha to use
     */
    public void setTintAlpha(float alpha) {
	setStatusBarAlpha(alpha);
	setNavigationBarAlpha(alpha);
    }

    /**
     * Apply the specified color tint to the system status bar.
     *
     * @param color
     *            The color of the background tint.
     */
    public void setStatusBarTintColor(int color) {
	if (mStatusBarAvailable) {
	    mStatusBarTintView.setBackgroundColor(color);
	}
    }

    /**
     * Apply the specified drawable or color resource to the system status bar.
     *
     * @param res
     *            The identifier of the resource.
     */
    public void setStatusBarTintResource(int res) {
	if (mStatusBarAvailable) {
	    mStatusBarTintView.setBackgroundResource(res);
	}
    }

    /**
     * Apply the specified drawable to the system status bar.
     *
     * @param drawable
     *            The drawable to use as the background, or null to remove it.
     */
    @SuppressWarnings("deprecation")
    public void setStatusBarTintDrawable(Drawable drawable) {
	if (mStatusBarAvailable) {
	    mStatusBarTintView.setBackgroundDrawable(drawable);
	}
    }

    /**
     * Apply the specified alpha to the system status bar.
     *
     * @param alpha
     *            The alpha to use
     */
    @TargetApi(11)
    public void setStatusBarAlpha(float alpha) {
	if (mStatusBarAvailable
		&& Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
	    mStatusBarTintView.setAlpha(alpha);
	}
    }

    /**
     * Apply the specified color tint to the system navigation bar.
     *
     * @param color
     *            The color of the background tint.
     */
    public void setNavigationBarTintColor(int color) {
	if (mNavBarAvailable) {
	    mNavBarTintView.setBackgroundColor(color);
	}
    }

    /**
     * Apply the specified drawable or color resource to the system navigation
     * bar.
     *
     * @param res
     *            The identifier of the resource.
     */
    public void setNavigationBarTintResource(int res) {
	if (mNavBarAvailable) {
	    mNavBarTintView.setBackgroundResource(res);
	}
    }

    /**
     * Apply the specified drawable to the system navigation bar.
     *
     * @param drawable
     *            The drawable to use as the background, or null to remove it.
     */
    @SuppressWarnings("deprecation")
    public void setNavigationBarTintDrawable(Drawable drawable) {
	if (mNavBarAvailable) {
	    mNavBarTintView.setBackgroundDrawable(drawable);
	}
    }

    /**
     * Apply the specified alpha to the system navigation bar.
     *
     * @param alpha
     *            The alpha to use
     */
    @TargetApi(11)
    public void setNavigationBarAlpha(float alpha) {
	if (mNavBarAvailable
		&& Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
	    mNavBarTintView.setAlpha(alpha);
	}
    }

    /**
     * Get the system bar configuration.
     *
     * @return The system bar configuration for the current device
     *         configuration.
     */
    public SystemBarConfig getConfig() {
	return mConfig;
    }

    /**
     * Is tinting enabled for the system status bar?
     *
     * @return True if enabled, False otherwise.
     */
    public boolean isStatusBarTintEnabled() {
	return mStatusBarTintEnabled;
    }

    /**
     * Is tinting enabled for the system navigation bar?
     *
     * @return True if enabled, False otherwise.
     */
    public boolean isNavBarTintEnabled() {
	return mNavBarTintEnabled;
    }

    private void setupStatusBarView(Context context, ViewGroup decorViewGroup) {
	mStatusBarTintView = new View(context);
	LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT,
		mConfig.getStatusBarHeight());
	params.gravity = Gravity.TOP;
	if (mNavBarAvailable && !mConfig.isNavigationAtBottom()) {
	    params.rightMargin = mConfig.getNavigationBarWidth();
	}
	mStatusBarTintView.setLayoutParams(params);
	mStatusBarTintView.setBackgroundColor(DEFAULT_TINT_COLOR);
	mStatusBarTintView.setVisibility(View.GONE);
	decorViewGroup.addView(mStatusBarTintView);
    }

    private void setupNavBarView(Context context, ViewGroup decorViewGroup) {
	mNavBarTintView = new View(context);
	LayoutParams params;
	if (mConfig.isNavigationAtBottom()) {
	    params = new LayoutParams(LayoutParams.MATCH_PARENT,
		    mConfig.getNavigationBarHeight());
	    params.gravity = Gravity.BOTTOM;
	} else {
	    params = new LayoutParams(mConfig.getNavigationBarWidth(),
		    LayoutParams.MATCH_PARENT);
	    params.gravity = Gravity.RIGHT;
	}
	mNavBarTintView.setLayoutParams(params);
	mNavBarTintView.setBackgroundColor(DEFAULT_TINT_COLOR);
	mNavBarTintView.setVisibility(View.GONE);
	decorViewGroup.addView(mNavBarTintView);
    }

    /**
     * Class which describes system bar sizing and other characteristics for the
     * current device configuration.
     *
     */
    public static class SystemBarConfig {

	private static final String STATUS_BAR_HEIGHT_RES_NAME = "status_bar_height";
	private static final String NAV_BAR_HEIGHT_RES_NAME = "navigation_bar_height";
	private static final String NAV_BAR_HEIGHT_LANDSCAPE_RES_NAME = "navigation_bar_height_landscape";
	private static final String NAV_BAR_WIDTH_RES_NAME = "navigation_bar_width";
	private static final String SHOW_NAV_BAR_RES_NAME = "config_showNavigationBar";

	private final boolean mTranslucentStatusBar;
	private final boolean mTranslucentNavBar;
	private final int mStatusBarHeight;
	private final int mActionBarHeight;
	private final boolean mHasNavigationBar;
	private final int mNavigationBarHeight;
	private final int mNavigationBarWidth;
	private final boolean mInPortrait;
	private final float mSmallestWidthDp;

	private SystemBarConfig(Activity activity,
		boolean translucentStatusBar, boolean traslucentNavBar) {
	    Resources res = activity.getResources();
	    mInPortrait = (res.getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT);
	    mSmallestWidthDp = getSmallestWidthDp(activity);
	    mStatusBarHeight = getInternalDimensionSize(res,
		    STATUS_BAR_HEIGHT_RES_NAME);
	    mActionBarHeight = getActionBarHeight(activity);
	    mNavigationBarHeight = getNavigationBarHeight(activity);
	    mNavigationBarWidth = getNavigationBarWidth(activity);
	    mHasNavigationBar = (mNavigationBarHeight > 0);
	    mTranslucentStatusBar = translucentStatusBar;
	    mTranslucentNavBar = traslucentNavBar;
	}

	@TargetApi(14)
	private int getActionBarHeight(Context context) {
	    int result = 0;
	    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
		TypedValue tv = new TypedValue();
		context.getTheme().resolveAttribute(
			android.R.attr.actionBarSize, tv, true);
		result = TypedValue.complexToDimensionPixelSize(tv.data,
			context.getResources().getDisplayMetrics());
	    }
	    return result;
	}

	@TargetApi(14)
	private int getNavigationBarHeight(Context context) {
	    Resources res = context.getResources();
	    int result = 0;
	    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
		if (hasNavBar(context)) {
		    String key;
		    if (mInPortrait) {
			key = NAV_BAR_HEIGHT_RES_NAME;
		    } else {
			key = NAV_BAR_HEIGHT_LANDSCAPE_RES_NAME;
		    }
		    return getInternalDimensionSize(res, key);
		}
	    }
	    return result;
	}

	@TargetApi(14)
	private int getNavigationBarWidth(Context context) {
	    Resources res = context.getResources();
	    int result = 0;
	    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
		if (hasNavBar(context)) {
		    return getInternalDimensionSize(res, NAV_BAR_WIDTH_RES_NAME);
		}
	    }
	    return result;
	}

	@TargetApi(14)
	private boolean hasNavBar(Context context) {
	    Resources res = context.getResources();
	    int resourceId = res.getIdentifier(SHOW_NAV_BAR_RES_NAME, "bool",
		    "android");
	    if (resourceId != 0) {
		boolean hasNav = res.getBoolean(resourceId);
		// check override flag (see static block)
		if ("1".equals(sNavBarOverride)) {
		    hasNav = false;
		} else if ("0".equals(sNavBarOverride)) {
		    hasNav = true;
		}
		return hasNav;
	    } else { // fallback
		return !ViewConfiguration.get(context).hasPermanentMenuKey();
	    }
	}

	private int getInternalDimensionSize(Resources res, String key) {
	    int result = 0;
	    int resourceId = res.getIdentifier(key, "dimen", "android");
	    if (resourceId > 0) {
		result = res.getDimensionPixelSize(resourceId);
	    }
	    return result;
	}

	@SuppressLint("NewApi")
	private float getSmallestWidthDp(Activity activity) {
	    DisplayMetrics metrics = new DisplayMetrics();
	    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
		activity.getWindowManager().getDefaultDisplay()
			.getRealMetrics(metrics);
	    } else {
		// TODO this is not correct, but we don't really care pre-kitkat
		activity.getWindowManager().getDefaultDisplay()
			.getMetrics(metrics);
	    }
	    float widthDp = metrics.widthPixels / metrics.density;
	    float heightDp = metrics.heightPixels / metrics.density;
	    return Math.min(widthDp, heightDp);
	}

	/**
	 * Should a navigation bar appear at the bottom of the screen in the
	 * current device configuration? A navigation bar may appear on the
	 * right side of the screen in certain configurations.
	 *
	 * @return True if navigation should appear at the bottom of the screen,
	 *         False otherwise.
	 */
	public boolean isNavigationAtBottom() {
	    return (mSmallestWidthDp >= 600 || mInPortrait);
	}

	/**
	 * Get the height of the system status bar.
	 *
	 * @return The height of the status bar (in pixels).
	 */
	public int getStatusBarHeight() {
	    return mStatusBarHeight;
	}

	/**
	 * Get the height of the action bar.
	 *
	 * @return The height of the action bar (in pixels).
	 */
	public int getActionBarHeight() {
	    return mActionBarHeight;
	}

	/**
	 * Does this device have a system navigation bar?
	 *
	 * @return True if this device uses soft key navigation, False
	 *         otherwise.
	 */
	public boolean hasNavigtionBar() {
	    return mHasNavigationBar;
	}

	/**
	 * Get the height of the system navigation bar.
	 *
	 * @return The height of the navigation bar (in pixels). If the device
	 *         does not have soft navigation keys, this will always return
	 *         0.
	 */
	public int getNavigationBarHeight() {
	    return mNavigationBarHeight;
	}

	/**
	 * Get the width of the system navigation bar when it is placed
	 * vertically on the screen.
	 *
	 * @return The width of the navigation bar (in pixels). If the device
	 *         does not have soft navigation keys, this will always return
	 *         0.
	 */
	public int getNavigationBarWidth() {
	    return mNavigationBarWidth;
	}

	/**
	 * Get the layout inset for any system UI that appears at the top of the
	 * screen.
	 *
	 * @param withActionBar
	 *            True to include the height of the action bar, False
	 *            otherwise.
	 * @return The layout inset (in pixels).
	 */
	public int getPixelInsetTop(boolean withActionBar) {
	    return (mTranslucentStatusBar ? mStatusBarHeight : 0)
		    + (withActionBar ? mActionBarHeight : 0);
	}

	/**
	 * Get the layout inset for any system UI that appears at the bottom of
	 * the screen.
	 *
	 * @return The layout inset (in pixels).
	 */
	public int getPixelInsetBottom() {
	    if (mTranslucentNavBar && isNavigationAtBottom()) {
		return mNavigationBarHeight;
	    } else {
		return 0;
	    }
	}

	/**
	 * Get the layout inset for any system UI that appears at the right of
	 * the screen.
	 *
	 * @return The layout inset (in pixels).
	 */
	public int getPixelInsetRight() {
	    if (mTranslucentNavBar && !isNavigationAtBottom()) {
		return mNavigationBarWidth;
	    } else {
		return 0;
	    }
	}

    }

}
